


A Fibonacci Romance

by Woldy



Category: Harry Potter - J. K. Rowling
Genre: F/F, Math Kink, Mathematics
Language: English
Status: Completed
Published: 2013-05-13
Updated: 2013-05-13
Packaged: 2017-12-11 18:30:33
Rating: General Audiences
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 1,593
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/801823
Author URL: https://archiveofourown.org/users/Woldy/pseuds/Woldy
Summary: <blockquote class="userstuff">
              <p>Flitwick is a neat linear equation. Trelawney is a negative number. Dumbledore appears chaotic, but she suspects there's an elegant solution. McGonagall is not easy to decode.</p>
            </blockquote>





	A Fibonacci Romance

**Author's Note:**

  * For [dexstarr](https://archiveofourown.org/users/dexstarr/gifts).



> Written for Dexstarr as part of the 2012 Informal HP femslash exchange. The prompt was "Minerva/Septima: numbers, relationship development, early days".

0  
Every letter Septima has received this year was delivered by an ibis, so it's a surprise when a small brown owl soars through her office window. She sees the familiar Hogwarts crest at the top, but it's not until Septima reads the words _"offer of employment as Professor of Arithmancy"_ that she understands.

She places the letter on her desk, and walks to the window. The view of Cairo is one of the best things about this office, and Septima looks out over millions of people and cars moving through streets where medieval mosques jostle against skyscrapers. Below her, people stream in and out of the tall bronze doors and a security guard clears a path for a gentleman with a magic carpet rolled up beneath his arm. A few miles further, out of sight, stand the pyramids.

Between her job as Senior Arithmancer here and previous posts in Doha and Johannesburg, it's been a decade since Septima was in Britain. Perhaps it's time she went home.

 

1  
Britain is much, much colder than she remembered. As the train winds it's way laboriously North from Kings Cross Station, Septima curses herself for not bringing a warmer coat, but she still can't tear herself from the window. The landscape that flashes by is all green hills, murky rivers, and grey sky; a colour palette forgotten after years of African sun. Septima watches it pass, searching for the patterns that will turn this strangeness into sense.

 

1  
"Welcome to Hogwarts," the woman says. She's an imposing figure clad in tartan, hair pulled into a severe bun beneath her hat. Her eyes are piercing, mouth a flat line, and Septima reflects the welcome is as chilly as the weather.

She's on the verge of asking when the woman adds: "I am Minerva McGonagall, Deputy Headmistress and Professor of Transfiguration. You may call me, Minerva."

"Hello, Minerva," Septima says, smiling and extending her hand. "Septima Vector. I suppose I'd better get used to being called Professor."

"It is customary at Hogwarts for the students to address Professors as such," Minerva says, prim and proper as a Gringotts goblin, and Septima stifles a smile. Perhaps this isn't as unfamiliar as she thought.

 

2  
At first Septima watches everything and says very little. She's been an arithmancer for long enough that it's second nature to make sense of the world by finding sequences and formulae.

Even the staff are amenable to mathematical analysis. Flitwick is a neat linear equation. Trelawney is a negative number. Dumbledore appears chaotic, but she's almost certain that the complexity will resolve into an elegant solution given enough data.

 

3  
Professor McGonagall is not easy to decode. On the surface she looks the same every day, wearing her bun and tartan the way a mollusc wears it's shell - with the impression of complete self-sufficiency and more than a hint that it doubles as armour. But is the shell more fragile than it looks? Just like a mollusc, Septima suspects that there is something softer, warmer, qualitatively different, underneath.

 

5  
Over time the rhythms of Hogwarts reveal themselves. The flow of students through corridors isn't so different to the momentum and surges of the stock market. Careful observation shows that the seemingly-random movement of the staircases is as logical as a traffic light.

With this new familiarity comes fondness. Just as understanding the numbers beneath the whoosh and sparkle of spellcraft makes magic even more beautiful.

 

8  
It comes to her one night as Septima is marking a pile of clumsy fifth year papers: Minerva is a Fibonacci sequence. She's neat, predictably repetitive, and tightly wound like a spiral - like a shell. Once the idea has come to her it can't be unseen again.

The candles have burned low by the time Septima has marked that first set of essays. She falls gratefully into bed and dreams of sand, shells, and the sound of the sea.

 

13  
Usually Septima loses interest in the object of her fascination once she had identified the pattern, but that doesn't happen with Minerva. There's always more to observe: the waveform that is the rise and fall of her voice, the curve of her mouth, her lean figure, the shapes drawn by her briskly moving hands... Overshadowing all those questions is the puzzle of what's beneath that neat, smooth surface.

Septima's porridge goes cold as she stares at the taut coil of hair at the back of Minerva's head. She imagines Minerva's hands twisting it into place and pinning it. She visualizes the tension easing and hair falling out of place as the pins are removed one by one.

 

21  
Somehow, without Septima realizing, her life at Hogwarts has stopped being strange and become a habit. She remembers the names of all her students and the timetable of her lessons, from the long, miserable Thursdays to the peace of Friday afternoons. Slowly she gets to know the staff and forges a tentative alliance with Aurora Sinistra.

This Friday, her afternoon is spent taking tea in Aurora's chambers. They talk about travel, Africa, the frustrations provoked by students, and Septima learns all manner of gossip.

"So none of the Professors are married?"

Aurora's eyes sparkle. "Only to their work" she says, in a thoroughly salacious tone. "Some of them don't exactly incline that way."

It takes Septima a moment of imaging lines fitting data points before it clicks. "You mean the fact that Dumbledore's gay?"

"Not just Dumbledore," Aurora says, pouring herself more tea.

Septima raises her ebebrows interrogatively, and Aurora takes a sip before leaning forwards to explain.

 

34  
It's even more difficult not to stare at Minerva after knowing that she's gay. Septima can't help calculating how close Minerva stands to Rolanda compared to Poppy, or assessing who Minerva smiles at with greatest regularity. It's none of her business, of course, but Septima has never been able to resist a puzzle, and she's starting to suspect that Minerva is the greatest puzzle of all.

Often, things that seem simple turn out to breathtakingly complex, from the fluid dynamics of air moving over a bird's wind to the whirling pressure of a storm front. Minerva is like that. The more Septima watches her, the more the layers of data create tensions and contradictions.

 

55  
The first time Minerva touches her is almost certainly an accident - just the brush of Minerva's hand against Septima's back as they pass in the doorway of the staffroom. It's hardly a touch at all. If it was anyone else then Septima wouldn't spare it a second thought.

At intervals all through the day Septima recalls the feel of Minerva's hand on her body and can't stifle a blush.

 

89  
Snow comes early this year, and is doubly inconvenient for arriving during the afternoon of the first Hogsmeade weekend. As Septima walks to Hogsmeade beside Filius and Aurora the snow swirls around them, their breath fogging the air, and children scurry past throwing snowballs.

"The perfect weather for a hot toddy," Pomona calls out cheerfully behind them.

By the time they leave the Three Broomsticks the snow is boot-deep and the street has been trampled down into ice. Septima nearly falls on her face only a few steps from the bar, and her dignity is only rescued by a couple of firm hands grabbing her waist.

"Careful," says an unmistakable Scottish lilt, and Septima looks back over her shoulder. Minervas gaze is even, meeting her eyes, but it is several seconds before she moves her hands.

"There's an art to walking in snow," Minerva continues, before Septima has managed to unjumble her brain. "You'll learn."

Septima doesn't quite muster the courage to say "Perhaps you can teach me," but Minerva stays by her side all the way home.

 

144  
The holidays come and go again with little fanfare, and before Septima realises it January is almost over. Septima has grown accustomed to the rhythm of life at Hogwarts now: meals in the Great Hall, classes, marking in the evenings, and the occasional friendly drink in the staff room.

Septima is tired and cold tonight, and she can't face the piles of grading that wait in her office. Instead, she pours herself a cup of tea and curls up in the armchair in front of the staff room fire. She'll just sit here for a moment, just long enough for a cuppa, and then go to work...

She is woken by a hand on her shoulder and a soft voice.

"You'll sleep better in your bed," Minerva murmurs, close to her ear, and Septima's eyes startle open.

It takes a minute for her to take it all in: the embers of the fire, guttering candles, cold tea, and Minerva leaning over her. Just for an instant, Minerva's eyes seem soft.

 

233  
With spring the world seems born anew: fresh grass underfoot, birdsong in the air, and the smell of fresh leaves. Septima is standing by the lake, her robes fluttering in the breeze, when Minerva touches her again: cool fingers circling her wrist. Like everything about Minerva the gesture is understated, but the intensity of it sends prickles of excitement across Septima's skin.

Warmth bursts inside her like a flower coming into bloom. No, not a flower; Septima has never been that fragile or colorful. She's more like the head of a fern unfurling, its leaves spreading wide in the sunlight.

Minerva lifts Septima's wrist and presses a gentle kiss to the center of her palm like a promise.

 

377 (and on)  
It's a promise they've kept.


End file.
